Mopar Rocker Arms

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hysteric
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Mopar Rocker Arms

Post by hysteric » Thu May 10, 2018 1:53 am

Does anyone make a small block Mopar rocker arm that bolts straight on and doesn't need the shafts raised or moved back to get good geometry via the mid lift method?

I have brand new Harland Sharps 1.6's and the scrub pattern is very wide. I've looked at 2 different heads and they both have the same issue.

Hysteric.

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Re: Mopar Rocker Arms

Post by paulzig » Thu May 10, 2018 4:30 am

Hughes make rocker stand shims, to raise them if that is what you need? I cant see the harm in raising, if it achieves a better scrub pattern, I did on mine..

I havent seen a specific mid-lift mopar rocker arm

hysteric
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Re: Mopar Rocker Arms

Post by hysteric » Thu May 10, 2018 6:05 am

Needs a lot more than shims i can tell you. :lol:

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Re: Mopar Rocker Arms

Post by BradH » Thu May 10, 2018 7:12 am

hysteric wrote:
Thu May 10, 2018 1:53 am
Does anyone make a small block Mopar rocker arm that bolts straight on and doesn't need the shafts raised or moved back to get good geometry via the mid lift method?
No.

Talk to Mike at B3 Racing Engines (Google) about the offset spacer kits he makes.

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Re: Mopar Rocker Arms

Post by hysteric » Thu May 10, 2018 7:23 am

Yeah I've seen the kit he offers. It certainly goes a long way to getting what have better but i would like to start at a better point than what i have.

Surely there has to be a rocker that's going to get me a lot closer than the H/S 's

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Re: Mopar Rocker Arms

Post by BradH » Thu May 10, 2018 10:49 am

Closer? Probably. But you'll only know if you have a variety of individual rockers from different companies to compare on a given head.

Liveable? Depends on what exactly you're willing to accept for geometry.

A bolt-on "improvement" for the geometry issues resulting from the OEM shaft c/l to valve relationship? IMO, that's where B3's relocation kits fit in.

It's not just an SBM issue; the BBM can have the same geometry "thing". Regardless, not everyone feels the need to address it. Sometimes I do, and sometimes I don't.

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Re: Mopar Rocker Arms

Post by andyf » Thu May 10, 2018 10:56 am

If you are going to work on a Mopar then you need to invest in a little rocker arm test jig like this one. This allows you to match up the available rocker arms with the cylinder head that you are working on. If you don't have something like this then you're just guessing when a new head comes in the door.
arms.jpg
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Re: Mopar Rocker Arms

Post by statsystems » Thu May 10, 2018 12:13 pm

It's not really a rocker arm issue, per se.

The issue is the way they mount. You can do like AndyF does and buy every brand of rocker there is and get it close or you can just fix it. Either way you need to fix it.

The issue is how the shafts mount. When you increase the the lift, increase the installed height, add a roller tip or any or all of that combination (and more) you'll never get the geometry correct with out moving the shafts. It's impossible.

That's why the W-2 heads were made with flat stands and used blocks. You can machine and/or shim the blocks and use offset blocks to fix the geometry.

It's sucks but it is what it is. One way or the other you'll have to move the shafts. And you can't just move them up like you already pointed out.


SS

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Re: Mopar Rocker Arms

Post by andyf » Thu May 10, 2018 2:55 pm

It depends on the cylinder head and the amount of valve lift. For low lift cams most any rocker arm will fit on most any head. For really high lift applications you'll probably need custom machine work. For bracket race type cams in the 0.600 to 0.800 lift range you can probably find a rocker arm that will fit the head without machine work but you might have to try 3 or 4 different rocker arms.

The rocker arm vendors don't tell you that rocker arm X will work with heads A,B or C for lift range Z to Y. It would be nice if they did that, but they don't. You just have to figure it out for yourself. If you call the vendor with a specific question and you know what you are talking about they will help you. The better the rocker arm the more likely it is that you'll find someone who can help. T&D and Jesel tend to have a really good understanding of what fits and works. The Chinese junk vendors won't have a clue if their stuff fits or works. They just want your credit card number and shipping address.
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Re: Mopar Rocker Arms

Post by hysteric » Thu May 10, 2018 6:19 pm

andyf wrote:
Thu May 10, 2018 10:56 am
If you are going to work on a Mopar then you need to invest in a little rocker arm test jig like this one. This allows you to match up the available rocker arms with the cylinder head that you are working on. If you don't have something like this then you're just guessing when a new head comes in the door.
arms.jpg
That's what i'm working on now. What is that 2nd one from the left Andy? Is that one of those Crane rockers that is no longer made?

It looks to be shorter than the rest.Does anyone have the Hughes or Comp cams rockers they can measure up for me?

Hysteric.

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Re: Mopar Rocker Arms

Post by statsystems » Thu May 10, 2018 6:39 pm

I think the one on the left is one that was offered by Don Gould at 4 seconds flat. I don't remember who made them. Then Crane, Hughes, Harlan Sharp, Crane ductile iron and what looks to be a PRW or a similar bushed stainless rocker.
Last edited by statsystems on Thu May 10, 2018 7:07 pm, edited 1 time in total.

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Re: Mopar Rocker Arms

Post by af2 » Thu May 10, 2018 6:45 pm

hysteric wrote:
Thu May 10, 2018 6:19 pm
andyf wrote:
Thu May 10, 2018 10:56 am
If you are going to work on a Mopar then you need to invest in a little rocker arm test jig like this one. This allows you to match up the available rocker arms with the cylinder head that you are working on. If you don't have something like this then you're just guessing when a new head comes in the door.
arms.jpg
That's what i'm working on now. What is that 2nd one from the left Andy? Is that one of those Crane rockers that is no longer made?

It looks to be shorter than the rest.Does anyone have the Hughes or Comp cams rockers they can measure up for me?

Hysteric.
A PM to Andy will save you from the internet head ache as in posts. The guy does it for a living and is one of the most helpfull out there!
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Re: Mopar Rocker Arms

Post by Geoff2 » Fri May 11, 2018 5:43 am

Erson cams used to make an adjustable ductile iron rocker for the SB Mopar, may still be available.

Also, the early 273 rockers were a similar design.

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Re: Mopar Rocker Arms

Post by Amilcar » Fri May 11, 2018 11:13 am

hysteric wrote:
Thu May 10, 2018 1:53 am
Does anyone make a small block Mopar rocker arm that bolts straight on and doesn't need the shafts raised or moved back to get good geometry via the mid lift method?

I have brand new Harland Sharps 1.6's and the scrub pattern is very wide. I've looked at 2 different heads and they both have the same issue.

Hysteric.
Sorry if I missed it wrote somewhere but,is yours rockers ### ?

Special Notes:
* Needle bearing allow for more oil flow to the rockers.
* Oil restrictors may be necessary to maintain oil pressure.
* Rockers are designed for big lift cams requiring .100 to .150 taller valves.
* Rocker shafts are drilled to allow for 3/8 mounting hardware.
* Rocker spring clearance is limited to 1.500 if more spring clearance is required,
contact our customer service department to discuss your options.

Thats info from Harland

I guess your using STD valve lenght height.

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